I could not understand all of my English because my English is not good yet.

1 . Weight

162 size 368g , 154size 365g , 146size 362g

2. Kingpin
Manufactured using special steel

3. heli-coiled
It was used to make up for the weak points of aluminium.

4. two type Trucks

{ MI arn eyo}My Korean isnt good either,{come sar mi dar }for the photos .Young is a korean first name.The plates do look like a thicker boen or galaxie
I have asked Australian koreans about roller and ice skating in korea but they didnt know much ,as the people i asked were restaraunters,not skaters.
Some of our local skaters compete in korea ,art and inline speed.
The king pins look like they are made from stainless then polished.
Have you tried vegimite yet?https://www.youtube.com/watch?v=ajqMnDcSf-Y.